Why Does Compost Produce Steam?

In the end compost is dirt. But how does it become dirt and why does it produce steam in the process?

Good questions.

I’m not a scientist but here’s the break down (get it? “break down”… oh never mind).

A compost pile could start from a pile of leaves or wood mulch or lawn grass clippings… or, many other things. These materials all contain carbon (often called “brown material”) and nitrogen (often called “green material”). Some materials are higher is carbon and others are higher in nitrogen. Both ingredients are needed for the pile to start the process of composting or decomposing.

Yes, decomposing… all living material can become dirt once it dies and is left to nature.

The compost pile has microbes. A microbe is a a microorganism. These microbes are alive and they are the reason a compost pile can decompose. These little critters start eating the material that are in the compost pile. In the process of eating and digesting they also give off heat as a byproduct. The moisture in the pile is heated up and turns to gas. This is the steam that can be seen as you turn a hot pile of compost.

There ya have it. A condensed science lesson that should raise more questions than it answers! Hey, I said I’m not a scientist 🙂

Here’s a video that shows a pile that is alive and steaming. We are adding dried leaves (carbon) to the hot pile of horse manure (nitrogen).

Compost Pile Steaming – Daddykirbs Garden Blog

for a more complete scientific explanation of what goes on in the process check this out: